Patterns of Weight Gain and Loss for Grizzly Bears in Northern Canada

  title={Patterns of Weight Gain and Loss for Grizzly Bears in Northern Canada},
  author={Michael C. S. Kingsley and John A. Nagy and Richard H. Russell},
Seasonal weight change in the grizzly bear (Ursiis arctos) in two populations in northern Canada was studied by fitting growth curves to spring and fall weights. The spring weight of females levels off soon after the average age of first reproduction; that of males continues to increase through maturity and eventually reaches nearly twice that of females. Males lost in winter 22% of their fall weight, the fraction changing very little with age. The weight change in females is much larger, and… 

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